1. Field Of The Invention
The invention generally relates to medical devices, and more specifically to a device for excising breast lesions.
2. Description Of The Prior Art
Breast cancer has been and continues to be a most serious problem. Because the disease can be so devastating, more and more women seek to be tested for early signs of any abnornal growths in their breasts. One common procedure for such testing is mammography. However, this approach has disadvantages. If the mammogram showns any indication of a growth the typical next step is to take a needle biopsy and have it analyzed to determine if the growth is malignant. If it is the woman and her physician must make a decision as to whether to remove the growth using surgery or use another method of treatment. Of the approximately 400,000 breast biopsies taken in the United States every year about 90% are benign. However, for those cases where the growth is malignant, the woman may be required to return for surgery at a later date. This interim period is very stressful and filled with anxiety and fear. Also, surgery, particularly, radical mastectomies, can be traumatic and debilitating. Because such surgeries are major procedures, these require extensive hospital stays.
More recently, radiologists have used stereotactic breast biopsy machines for obtaining more accurate images of the abnormal growths. However, once found the same procedures were followed as with mammograms. The same is true with a laser scanning cytometer (LSC) developed by CompuCyte Corporation based in Cambridge, Mass., which appears to have the potential to advance the prognosis and management of breast-cancer patients. Unfortunately, when a malignant lesion has been removed and there is no lymph node involvement, traditional prognastic indicators such as tumor size and lymph node involvement are not accurate predictors of recurrence. Pathologists may need to look at cell cycle and cell proliferation analyses to identify which node-negative patients are at high risk for recurrence and therefore require close observation.
A number of surgical devices have been proposed for removing material from a patient without the use of conventional surgery. Compressible/expandable atherectomy cutters are disclosed in U.S. Pat. Nos. 4,966,604; 5.192,291; and 5,224,945. The prior art teaches flexible blades bent outwardly, the amount of expansion being controlled by a control element which can adjust the drive element through an infinite variety of positions while the blade rotates. A similar endovascular cutter for removing lesions constricting a vascular channel is disclosed in U.S. Pat. No. 5,318,576.
In U.S. Pat. No. 3,618,611 a vacuum rotary dissector is disclosed which is used for removing undesired tissue during surgery from difficult to reach locations. However, this dissector does not use compressible/expandable cutters.